Since the dynamic range and color depth is so good in RAW, I have cheated before where I take one .CR2 image and export it out of ACR at three different exposures. Later I use Photomatix Pro to generate a very nice HDR. I have also done this with Timelapse images by importing them to ACR and generating the three exposures which are then batch joining them, three at a time, to make a pseudo HDR Timelapse. This works pretty good...
Now with these .CR2 files, each one has a preset exposure that make the Timelapse Flicker Free.. The problem I have is now to raise say 1 EV to all images, then export them, then lower exp by -2 EV, then export them. Finally I merge the original with the +1, -2 to make new HDR image. So I need a software that take the current corrected exposure and change all of them at the same time or via a script.
Maybe LRTimelapse can do this but I have not used it before.